Building block wiper



FIG. 1 is a front perspective view of showing a building block wiper;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a rear view thereof; and,

FIG. 7 is a right side view thereof, a left side view not being shown as it is a mirror image of the right side view. 

CLAIM The ornamental design for a building block wiper, as shown and described. 